Electrical systems typically use a number of integrated circuits that are mounted on a printed circuit board. The individual integrated circuits of the system are typically fabricated on different wafers. Each wafer is tested and separated into individual dies or chips. Individual chips are then packaged as individual integrated circuits. Each integrated circuit includes a number of leads that extend from the packaging of the circuit. The leads of the various integrated circuits, are interconnected to allow information and control signals to be passed between the integrated circuits such that the system performs a desired function. For example, a personal computer includes a wide variety of integrated circuits, e.g., a microprocessor and memory chips, that are interconnected on one or more printed circuit boards in the computer.
While printed circuit boards are useful for bringing together separately fabricated and assembled integrated circuits, the use of printed circuit boards creates some problems which are not so easily overcome. For example, printed circuit boards consume a large amount of physical space compared to the circuitry of the integrated circuits which are mounted to them. It is desirable to reduce the amount of physical space required by such printed circuit boards. Further, assuring the electrical integrity of interconnections between integrated circuits mounted on a printed circuit board is a challenge. Moreover, in certain applications, it is desirable to reduce the physical length of electrical interconnections between devices because of concerns with signal loss or dissipation and interference with and by other integrated circuitry devices.
A continuing challenge in the semiconductor industry is to find new, innovative, and efficient ways of forming electrical connections with and between circuit devices which are fabricated on the same and on different wafers or dies. Relatedly, continuing challenges are posed to find and/or improve upon the packaging techniques utilized to package integrated circuitry devices. As device dimensions continue to shrink, these challenges become even more important.
For reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for an improved technique for interconnecting individual integrated circuits in an electronic system.